Negative electrode composite material as well as preparation method and application thereof

The invention provides a negative electrode composite material and a preparation method and application thereof. The negative electrode composite material comprises an ultramicro N-type silicon crystal material and a conductive carbon material, and the ultramicro N-type silicon crystal material is dispersed in the conductive carbon material; the ultramicro N-type silicon crystal material is not exposed on the outer surfaces of the negative electrode composite material particles, and the D50 particle size of the ultramicro N-type silicon crystal material is less than or equal to 5nm. The negative electrode composite material is good in structural stability, has relatively high conductivity, relatively good rate capability, good expansion characteristic and cycle performance, and can be used for providing an electrochemical device with good rate capability and cycle performance. 本申请提供了一种负极复合材料及其制备方法、应用。所述负极复合材料包括超微N型硅晶材料和导电碳材料，所述超微N型硅晶材料弥散在所述导电碳材料中；所述负极复合材料颗粒的外表面未暴露有所述超微N型硅晶材料，且所述超微N型硅晶材料的D50粒径小于或等于5nm。该负极复合材料的